Laminate bonded with an adhesive waxy telomer of ethylene on pseudocumene

ABSTRACT

LAMINATING WAX OF HIGH ADHESIVE CHARACTERISTICS ESPECIALLY USEFUL IN THE PRODUCTION OF INTERCALATED PRODUCTS IS OBTAINED FROM TELOMER RESULTING FROM A TELOMERIZATION EMPLOYING PSEUDOCUMENE AS THE TELEGEN AND ETHYLENE AS THE TAXOGEN, THE REACTION PRODUCING SAID TELOMER BEING HEREINAFTER REFERRED TO AS THE TELOMERIZATION OF ETHYLENE ON PSEUDOCUMENE.

y 1972 E. P. BLOCK LAMINATE BONDED WITH AN ADHESIVE WAXY TELOMER OFETHYLENE ON PSEUDOCUMENE Original Filed April 12. 1968 mPwuIm UnitedStates Patent U.S. Cl. 161-235 Claims ABSTRACT OF THE DISCLOSURELaminating wax of high adhesive characteristics especially useful in theproduction of intercalated products is obtained from telomer resultingfrom a telomerization employing pseudocumene as the telegen and ethyleneas the taxogen, the reaction producing said telomer being hereinafterreferred to as the telomerization of ethylene on pseudocumene.

CROSS REFERENCE TO RELATED APPLICATION This is a division of applicationSer. No. 720,832, filed Apr. 12, 1968.

BACKGROUND OF THE INVENTION The preparation of intercalated productsfrom materials in the form of relatively thin layers, films, or sheetscalled laminations is widely practiced with a considerable variety ofmaterials, such as those of cellulosic composition, of which cellophane,pasteboard, cardboard, paper and cotton cloth in their various forms areoutstanding examples. A wide variety of sheet materials of syntheticcomposition also are used, a typical example berngpolyethylene. Strongadhesiveness is assiduously sought in the wax employed.

The telomerization of benzenoid hydrocarbons, including pseudocumene,with ethylene is taught in U.S. Pat. No. 3,206,519. As between thetelogen pseudocumene (l,2,4-trimethylbenzene) and closely relatedtelogens, such as, mesitylene (1,3,5-trimethylbenzene), and xylene (amixture of dimethylbenzenes), surprisingly wide differences in theadhesive properties of comparable wax fractions of the resultingtelomers have been discovered. To illustrate, and upon employing thestandardized test described in lines 25-54, column 2 of U.S. Pat.2,746,910, relevant fractions obtained from telomers of ethylene onpseudocumene had adhesion values within the range of 70-160 grams,whereas relevant fractions of telomers of ethylene on mesitylene hadadhesion values within the range of 3-4, and relevant fractions oftelomers of ethylene on mixed xylenes had adhesion values of 7-19. Arelevant fraction of a telomer of ethylene on para-xylene had anadhesion value of 11. A telomer of ethylene on benzene yielded arelevant fraction having an adhesion value of only 2.

SUMMARY OF THE INVENTION The invention resides in a laminating wax whichis a telomer of ethylene on pseudocumene, and which has cooling curvemelting point in the range of 135-155 F.

as determined by test method A.S.T.M. D-87, or its equivalent; apenetration, as determined by A.S.T.M. test method D-1321, in the rangeof 18-30 at 77 F., in the range of 28-40 at 90 F., and in the range of32-56 at 100 F.; a viscosity at 210 F., as determined by A.S.T.M. testmethod D-2161, in the range of 70-76 SUS; an average molecular weight,as determined by the vapor pressure osmometer method, A.S.T.M. D-2503,

in the range of 550-750; and in an adhesion value, as determined by thestandardized test method described in U.S. Pat. 2,746,910, of at leastgrams.

Preferably, melting points fall between 145-155 F.; pentrations between20-26 at 77 F., between 33-40 at 90 F., and between 35-50 at 100 F.;viscosities at 210 F. between 70-74 SUS; average molecular weightsbetween 600-700; and adhesion values of at least all determined by thetest methods set forth in the previous paragraph.

The invention also resides in a particularized method for producing thebasic telomer product in combination with steps for separating the abovenew laminating wax from said basic telomer product, which steps involvesolvent fractionation, particularly after removal of light ends bydistillation.

In addition the invention resides in the new laminated product resultingfrom the use of the new laminating wax of the invention.

BRIEF DESCRIPTION OF THE DRAWING In the drawing, the single figurerepresents an intercalated product of the invention, and wherein 1 and 3represent laminations, such as of paper or otherwise, between which isintercaltaed a layer 2 of laminating wax of the invention.

DESCRIPTION OF THE INVENTION Although the telomer of ethylene onpseudocumene from which the laminating wax of the invention is separatedcan be prepared otherwise, it is preferred that it be prepared underparticularized conditions falling within the teachings in Eberhardt U.S.Pat. No. 3,206,519, and to be hereinafter more particularly pointed out.

In a typical preparation of the crude telomer, pseudocumene and ethyleneare brought into contact in the presence of a catalyst which is acombination of a nonaromatic tertiary amine, which is a chelatingdiamine or a bridgehead amine, with LiR, wherein R is a hydrocarbonradical which preferably is alkyl having 2-10 carbon atoms; said contacttaking place 1) with the pseudocumene (including its reaction products)present in the reaction zone in at least 50 percent, preferably at least75 percent, concentration by volume, and (2) under temperatureconditions in the range 50-130 C., preferably -110 C., and (3) withethylene pressure in the reaction zone in the range of 200-400 p.s.i.g.,preferably 250-350 p.s.i.g.

Also typically, the amine is present in the catalyst combination in atleast equimolar amount relative to the HR component and preferably asubstantial molar excess of the amine is used.

Examples of chelating diamines are N,N,N',N'-tetramethylethylenediamine, N,N,N',N'-tetrapropylethylene 3 diamine, N,N,N',N'tetraalkyl-1,2-diaminocyclohexane, N,N'-dialkylbispidin and sparteine.

Examples of amines in which one or more of the nitrogen atoms are at abridgehead position, that is with all three valences of the nitrogenparticipating in the ring system, are triethylene diamine, quinuclidine,and the amadamantanes which structurally resemble adamantane, exceptthat one or more nitrogen atoms are substituted at bridgehead positionsin place of carbon.

In carrying out the reaction, it is well to keep in mind thefollowing'theoretical considerations as guidelines.

The first step in initiating the reaction involves the transfer of a.lithium atom from the catalyst complex to a pseudo-cumene molecule, andreplacement of a hydrogen atom thereon by the Li, the hydrogen atomreplaced be ing by reaction preference a primary hydrogen atom on one ofthe methyl side chains. The next step is the propagation of a chain bythe addition of ethylene molecules between the Li atom and the adjacentcarbon atom, the Li atom continuing to be located at the end of thechain. Finally, this telomerization reaction will terminate due totransmetallation whereby the Li atom at the end of the chain transferswith a new hydrogen atom in the same manner as initially occurred. Thenewly formed reaction site then undergoes chain growth in a new reactioncycle, and the mechanism is repeated.

A multiplicity of such reactions taking place simultaneously on the sameand on different pseudocumene molecules can be visualized. It can alsobe visualized that reaction can take place at an unsubstituted ringcarbon atom of the pseudocumene molecule and chain growth therefromtakes place. And, since the conditions of reaction favortransmetallation over propagation, substantial transference of Li atomswith additional hydrogen atoms on the alpha carbon atoms of the sidechains is visualized as well as a contributing factor to the outstandingcharacteristics of the lamination wax produced.

The length of chain growth depends upon the rate of the propagationreaction relative to the rate of the transmetallation reaction, sincethe latter functions to terminate the former.

The rate of propagation depends largely on the ethylene pressureemployed, increasing with ethylene pressure, while the transmetallationreaction is largely unaffected, if at all, by ethylene pressure.

On the other hand, the rate of transmetallation increases withincreasing concentration of pseudocumene (including its reactionproducts) in the reaction zone.

In the production of crude telomer to which this invention relates, therate of the propagation reaction relative to the rate of thetransmetallation reaction is so controlled, e.g., within the reactionconditions set forth in detail above, to yield a laminating wax fractionof the specifications herein described and claimed.

Thus to produce a telomer having a laminating wax fraction with (l)cooling curve melting point, (2) penetration, (3) viscosity, and (4)average molecular weight, specifications of a character as set forthabove, and with (5) adhesion values as set forth, the rate ofpropagation relating to the rate of transmetallation is held in. check,thus limiting the length of average individual chain growth, by placinga maximum on ethylene pressure, while at the same time assuring asufiiciently high average individual chain length by placing a minimumon said pressure, with the rate of transmetallation coordinatedlyrelatively high by virtue of high concentration of pseudocumene(including its reaction products) in the reaction zone, so that due tointeraction of said reaction rates, a type of substituted pseudocumenewax molecule is built up having the high adhesion values herein setforth.

While temperature conditions during the reaction are not as critical asthe above factors, for all around good results, those set forth ought tobe observed.

It will be understood that there is a variation in the chain length, andmost probably also a variation in the number of propagated chains, onindividual molecules of the telomer including its wax fraction, so thatboth the parent telomer and its fractions comprise a mixture ofalkylbenzenes having, insofar as the wax fraction is concerned, a rangein cooling curve melting points, penetrations, viscosities, andmolecular weights, a consideration which from the standpoint ofidentification is met as to the overall laminating wax by the recitationof test methods herein, whereby the laminating wax of the inven tion canbe fully and completely identified.

Pseudocumene being a liquid, the reaction can be carried out in theabsence or in the presence of a solvent of which hexane, cyclohexane,octane, decane and the like are examples, attention being given toconcentration considerations herein set forth.

Separation of the laminating wax from the telomer obtained, such asdescribed above, can be carried out in any desired manner. A typicalprocedure of the invention involves, as an initial step, distillation atreduced pressure to remove the most volatile portion of the reactionproduct, unreacted reactants, and any solvent present. This is followedby dissolving, at elevated temperature, the waxy residuum in a solvent,for example, n-hexane. The resulting solution is cooled slowly toprecipitate a hard polishtype wax which is removed by filtration. Thefiltrate obtained is now further cooled slowly to precipitate thelaminating wax fraction which, after recovery by filtration, issubjected to treatment for solvent removal, e.g., by use of elevatedtemperature, reduced pressure, and/or nitrogen stripping. The finalfiltrate contains a petrolatum-like material which, if desired, can berecycled to the telomerlzatron reaction zone.

Other solvents may be employed in place of n-hexane for separating fromthe telomer the desired laminating wax fraction. To illustrate, alaminating wax fraction of exceptionally high adhesiveness was obtainedfrom pseudocumene-ethylene telomers using a mixture of 40% benzene-60%methyl ethyl ketone as solvent.

The laminating wax, being a mixture of alkylbenzenes of differentmelting points, penetrations, viscosities and molecular weights, hasproperties which are a composite function of the properties of theindividual alkylbenzenes present, and their relative concentrations.

Generally speaking, for any given solvent, solubilities of thealkylbenzenes increase with decrease in melting point, penetration,viscosity and molecular weight, and vice versa. Also solubilitiesincrease with increase in temperature, and vice versa, the amount heldin solution being a function of solvent concentration, increasing within crease in solvent concentration, and vice versa.

These and other considerations are so well known and understood in theart of solvent fractionation as not to require further elaboration, andit is by following wellestablished principles in the practice of thisart that wax fractions having properties falling within the broad and!or specific ranges set forth above are obtained from the crude telomer.Accordingly it is to be understood that the following examples are givenby way of illustration.

Example I A stainless steel reactor with agitator and of 1 litercapacity was employed. This was charged with 200 ml. of pseudocumene, 20ml. of a 1.65 molar solution of butyl lithium in cyclohexane, and 5 ml.of N,N,N',N'- tetramethylethylene diamine, and then warmed to 60 C. Thereactor was pressured to 300 p.s.i.g. with ethylene, and the temperatureallowed to come up to -l00 C., wlth agitation of the reaction mixtureand some application of heat. The reaction was permitted to proceed forapproximately 4 hours, whereupon the ethylene source was disconnected,and the catalyst killed, as by the additron of water, after permittingthe reactor to cool, and the venting of residual gas. The reactionmixture was washed with water to remove catalyst residues. Upon removalof solvent and any unreacted pseudocumene by distillation 373 grams ofalkylbenzene product were obtained.

From the foregoing product, 273 grams of relatively volatile oil weredistilled off, leaving 100 grams for solvent fractionation. Of thelatter, 92.5 grams were dissolved in 920 ml. of n-hexane heated to nearits boiling point for solution purposes. After solution was complete,the mixture was slowly cooled to 80 F., and the precipitate, a hardpolish-type wax, was separated by filtration, with the precipitate beingwashed with n-hexane to recover adhering laminating wax.

The combined filtrate and washings were now slowly cooled to 36 F., andthe precipitate recovered by filtration and n-hexane washing. The latterprecipitate, comprising the laminating wax of the invention, wassubjected at elevated temperature to nitrogen stripping to removeresidual solvent.

This laminating wax had a melting point of 150; penetrations by A.S.T.M.D-1321 at 77 F. of 24, at 90 F. of 34, and at 100 F. of 40; a viscosityat 210 F. A.S.T.M. D-445 of 13.8 cs., and by A.S.T.M. D-2161 of 73 SUS,an average molecular weight (M,,) of 650, and an adhesion (grams/2"strip of 84. The yield was 22.7 grams.

The oil initially distilled from the reaction mass, and thepetrolatum-like wax recovered from the final filtrate, find utility,among other things, by way of recycle back to the zone oftelomerization, for further reaction into higher molecular weightmaterial.

Example II A stainless steel reactor with agitator and of 1 litercapacity was employed. This was charged with 200 ml. of pseudocumene, 20ml. of a 1.65 molar solution of butyl lithium in cyclohexane, and 5 ml.of N,N,N',N'- tetramethylethylene diamine, and then warmed to 60 C. Thereactor was pressured to 300 p.s.i.g. with ethylene, and the temperatureallowed to come up to 95-l00 C., with agitation of the reaction mixtureand some application of heat. The reaction was permitted to proceed forapproximately 4 hours, whereupon the ethylene source was disconnected,and the catalyst killed, as by the addition of water, after permittingthe reactor to cool, and the venting of residual gas. The reactionmixture was washed with water to remove catalyst residues. Upon removalof solvent and unreacted pseudocumene by distillation 317 grams ofalkylbenzene product were obtained.

From the foregoing product, 229 grams of relatively volatile oil weredistilled off, leaving 88.7 grams for solvent fractionation. Of thelatter, 78.9 grams were dissolved in 800 ml. of n-hexane heated to nearits boiling point for solution purposes. After solution was complete,the mixture was slowly cooled to 80 F., and the precipitate, a hardpolish-type wax, was separated by filtration, with the precipitate beingwashed with n-hexane to recover adhering laminating wax.

The combined filtrate and washings were now slowly cooled to 36 F., andthe precipitate recovered by filtration and n-hexane washing. The latterprecipitate, comprising the laminating wax of the invention, wassubjected at elevated temperature to nitrogen stripping to removeresidual solvent.

This laminating wax had a melting point of 149; penetrations by A.S.T.M.D-l321 at 77 F. of 25, at 90 F. of 38, and at 100 F. of 47; a viscosityat 210 F. by A.S.T.M. D-445 of 13.8 cs., and by A.S.T.M. D'-2161 of 73SUS, an average molecular weight (M of 650, and an adhesion (grams/2"strip) of 76. The yield was 16.1 grams.

Example III A stainless steel reactor with agitator and of 1 litercapacity was employed. This was charged with 400 ml. of pseudocumene, 40ml. of a 1.65 molar solution of butyl lithium in cyclohexane, and ml. ofN,N,N',N'- tetramethylethylene diamine, and then warmed to 60 C.

The reactor was pressured to 300 p.s.i.g. with ethylene, and thetemperature allowed to come up to -100 C., with agitation of thereaction mixture and some application of heat. The reaoton was permittedto proceed for approximately 4 hours, whereupon the ethylene source wasdisconnected, and the catalyst killed, as by the addition of water,after permitting the ractor to cool, and the venting of residual gas.The reaction mixture was washed with water to remove catalyst residues.Upon removal of solvent and unreacted pseudocumene by distillation 733grams of alkylbenzene product were obtained.

From the foregoing product, 548 grams of relatively volatile oil weredistilled off, leaving 185 grams for solvent fractionation. Of thelatter, 172 grams were dissolved in 1000 ml. of 40% benzene-60% methylethyl ketone solvent heated to near its boiling point for solutionpurposes. After solution was complete, the mixture was slowly cooled to113 F., and the precipitate, a hard polish-type wax, was separated byfiltration, with the precipitate being washed with the above solventmixture to recover adhering laminating wax.

The combined filtrate and washings were now slowly cooled to 55 F., andthe precipitate recovered by filtration and washing with the above'solvent mixture. The latter precipitate, comprising the laminating waxof the invention, was subjected at elevated temperature to nitrogenstripping to remove residual solvent.

This laminating wax had a melting point of 149; penetrations by A.S.T.M.D-l321 at 77 F. of 21, and at F. of 39; a viscosity at 210 F. byA.S.T.M. D-445 of 13.4 cs., (71.7 SUS), an average molecular weight (Mof 646, and an adhesion (grams/2" strip) of 150. The yield was 22.7grams.

Substitution in the above examples of variables within the teachings ofthis specification yields comparable results.

On the other hand, a significant departure therefrom yieldssignificantly poorer results.

The case of mesitylene, which represents a mere shift in position of oneof the three methyl groups On the benzene ring as compared topseudocumene, has already been pointed out. In a run which was a virtualduplicate of Example I, but with mesitylene as telogen instead ofpseudocumene, the adhesion value of the relevant wax fraction was 4. Arerun of Example III under virtually the same conditions, but with theethylene pressure increased to 600 p.s.i.g., dropped the adhesion valueto 10, and a rerun of Example I under virtually the same conditions,except that closed to twice the volume of n-hexane based on telogen, wasadded to the reaction zone, dropped the adhesion value to 62.

The outstanding contribution to the art made by the invention is thusabundantly demonstrated.

In this specification and in the claims, values given for 1) coolingcurve melting point, (2) penetration, (3) viscosity, (4) molecularweight, and (5) adhesion are as determined by test methods as follows:

(1) Cooling curve melting pointA.S.T.M. D-87 or equivalent method (2)PenetrationA.S.T.M. D-1321 (3) ViscosityA.S.T.M. D-2l61 (4) MolecularweightVapor phase osmometer method A.S.T.M. D-2503 (5)Adhesion-Procedure set forth in lines 25-54, column 2 of US. Pat.2,746,910

I claim:

1. A laminated material comprising at least two laminae adhered togetherby a film of laminating wax, said laminating wax comprising a telomer ofethylene on pseudocumene, said wax having a cooling curve melting pointin the range of -155 F.; a penetration at 77 F. in the range of 18-30,at 90 F. in the range of 28-40, and at 100 F. in the range of 32-56; aviscosity at 210 F. in the range of 70-76 SUS; an average molecularweight in the range of 550-750; and an adhesion value of at least 70grams.

2. The laminated material of claim 1 in which the laminae are ofcellulosic composition.

3. A laminated material comprising at least two laminae adhered togetherby a film of laminating wax, said laminating wax comprising a telomer ofethylene on pseudocumene, said wax having a cooling curve melting pointin the range of 145-155 F.; a penetration at 77 F. in the range of20-26, at 90 F. in the range of 33-40, and at 100 F. in the range of3550; a viscosity at 210 F. in the range of 70-74; an average molecularweight in the range of 600-700; and an adhesion value of at least 75grams.

4. The laminated material of claim 3 in which the laminae are ofcellulosic composition.

References Cited UNITED STATES PATENTS 10/1954 Field et a1. 260-79.3 R12/ 1955 Closson et al 260-668 B 3/1962 Butler 99-171 12/1963 Emrick etal. 25259 9/ 19'65 Eberhardt 260268 R 7/1969 Langer 260668 B U.S. Cl.X.R.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 ,665,618 Dated May 30, 1972 Inventor(s) Ernest P. Black It is certified thaterror appears in the above-identified patent and that said LettersPatent are hereby corrected as shown below:

It is requested that the name Ernest P. BLOCK be changed to Ernest P.BLACK.

Signed and sealed this 17th day of October 1972.

(SEAL) Attest:

EDWARD M.FLETC 2HER,JR. ROBERT GOTTSCHALK Attesting Officer Commissionerof Patents ORM PO-IOSO (10-69) USCOMM-DC 6O376P59 U.S. GOVERNMENTPRINTING OFFCE 1969 O-366-334

